Interpretive Summary: The last two decades have produced a better understanding of insect-microbe associations and yielded some important opportunities for insect control. However, most current knowledge comes from model systems. Thrips have been understudied despite their global importance as invasive species, plant pests and disease vectors. Using next-generation DNA sequencing and bacterial identification methods, we surveyed the bacteria of the globally important pest, chilli thrips. The most abundant bacterial taxa identified were Actinobacteria and Proteobacteria and a total of 189 genera of bacteria were identified. The absence of any bacteria commonly found to be transferred from mother to offspring in insects is consistent with other studies suggesting that thrips primarilly acquire microbes from their environment. Future work should determine the nature of these associations.

Technical Abstract:
The last two decades have produced a better understanding of insect-microbial associations and yielded some important opportunities for insect control. However, most of our knowledge comes from model systems. Thrips (Thysanoptera: Thripidae) have been understudied despite their global importance as invasive species, plant pests and disease vectors. Using a culture and primer independent next-generation sequencing and metagenomics pipeline, we surveyed the bacteria of the globally important pest, Scirtothrips dorsalis Hood. The most abundant bacterial phyla identified were Actinobacteria and Proteobacteria and the most abundant genera were Propionibacterium, Stenotrophomonas, and Pseudomonas. A total of 189 genera of bacteria were identified. The absence of any vertically transferred symbiont taxa commonly found in insects is consistent with other studies suggesting that thrips primarilly acquire resident microbes from their environment. This does not preclude a possible beneficial/intimate association between S. dorsalis and the dominant taxa identified and future work should determine the nature of these associations.